1. Field of the invention
The present invention relates to a flexibly resilient sealing member for placement inside an oil filter assembly, and to an oil filter assembly incorporating same. More particularly, the present invention relates to a sealing member having integral pressure relief valves formed therein, avoiding the need for supplemental pressure relief valves in a filter assembly, and to an oil filter assembly which incorporates the novel sealing member.
2. Description of the Background Art
Oil filters of many varieties are known. Some of these known oil filters incorporate flexibly resilient pressure relief valve members. Pressure relief valves are included in substantially all oil filter assemblies, to provide circulating engine oil an alternative route through an oil filter when a filter element is restricted due, for example, to dirt accumulation in the filter, or to high oil viscosity at a low operating temperature, such as on a cold start in a winter climate.
Some examples of known designs for oil filter assemblies can be found in U.S. Pat. No. 3,785,491 (Dudinec et al.), U.S. Pat. No. 4,127,484 (Walulik et al.), U.S. Pat. No. 4,747,378 (Cantoni), U.S. Pat. No. 5,271,429 (Bauer et al.), U.S. Pat. No. 5,284,579 and U.S. Pat. No. 5,405,527 (Covington), U.S. Pat. No. 5,584,987 (Mules) and U.S. Pat. No. 5,690,816 (Covington).
Although many designs for oil filter assemblies are known, a need still exists in the art for a relatively simple, straightforward and inexpensive sealing member for use in an oil filter assembly, which will provide an alternative route for oil to follow, to allow the oil to continue circulating through a filter assembly when restriction through the filter element exceeds a certain value, yet which will avoid the necessity of a conventional oil pressure relief valve having a mechanical spring therein. Preferably, such a sealing member would be economical to produce, and would lend itself to high-volume manufacturing operations.